Re: body panel thickness
Though I've never purchased any repro panels, I have read many posts saying that they are thinner than stock. 22 ga is .030" and you just need to use caution welding it. Will you be doing that yourself? The preferred method of joining panels is butt welding them with a good MIG welder. Doing so with 22 ga will be a little more tricky; you need to be very attentive to controlling your heat or it can warp more easily than a thicker panel. Also, when striking the arc initially, you want your electrode (tip of the wire) to be favoring the thicker metal ever so slightly, then drift toward the thinner piece after hitting the trigger. Otherwise you can end up blowing a hole through the edge of the thinner panel.
'71 Chevelle; stout 355/TH350 (full manual)/12 bolt posi, 4.11